The AGM-78 Standard ARM was a medium-range air-to-surface guided missile developed from the RIM-66 Standard MR by General Dynamics for the US Navy and the US Air Force. The AGM-78 was guided by the radar energy emitted by the target. Thus, the Standard ARM was designed to strike North Vietnamese radars that controlled anti-aircraft guns and missiles. The acronym “ARM” stands for “anti-radiation missile”. It was used during the Vietnam War and usually launched from an F-4G, F-105, or A-6 aircraft.
The AGM-78 first version, the A1 Model 0, was little more than an air-launched RIM-66 with the Shrike’s anti radar seeker head attached to the front. Fitted with a blast-fragmentation warhead, this variant was powered by an Aerojet Mark 27 MOD 4 dual-thrust solid rocket. Although it was more effective and destrutive, the AGM-78 was much more expensive than the AGM-45 and the Shrike continued in service for some time.
General Dynamics made modifications to the Standard, obtaining three more versions with improved electronic counter-countermeasures and more precise and selective seekers. More than 700 AGM-78 missiles were produced until 1978. Thus, in 1969 an improved model called the AGM-78B entered into service. This featured a broadband seeker which allowed the missile to be used against a much wider variety of targets without having to select the seeker before the mission. Between 1973 and 1976 General Dynamics introduced the AGM-78D, which was fitted with a new motor. A follow up missile, the AGM-78D2, had an active optical fuze, still greater reliability, and a new 100 kg (220 lb) blast-fragmentation warhead.
Specifications for the AGM-78 Standard
Diameter : 1 foot 1½ inches (343 mm)
Length : 15 ft (4.6 m)
Finspan : 3 feet 3½ inches (1.00 m)
Weight : 1,350–1,800 lb (610–820 kg) depending on model
Engine: Aerojet Mk 27, Mod 4 solid rocket motor
Warhead : 100 kg (220 lb) blast-fragmentation type
Fusing : Active optical proximity type
Range : Up to 70 miles (100 km)
Speed : Mach 2.0
AGM-78 Standard (Video)